Technical Field
The present disclosure relates to cannula assemblies and their method of manufacture. More particularly, the present disclosure relates to blunt tip cannula assemblies for accessing a vial and their method of manufacture.
Description of Related Art
In the medical field, fluid transfer devices, particularly, vial access devices are commonly used to draw medicaments from medical vials in order to fill syringes. Medical vials are well known in the medical field and typically include a pierceable septum and a body defining a reservoir for containing a medicinal fluid. Vial access devices typically include a syringe having a syringe body, a plunger assembly, and a needle or cannula hub assembly. Typically, the cannula assembly includes a hollow needle or cannula configured to pierce a septum of a vial and a needle hub which can be removably attached to the syringe body. The needle or cannula can be formed from metal or plastic. After medical fluid has been withdrawn from a medical vial into the syringe, the needle hub assembly can be removed from the syringe body, such that, an intravenous catheter or a syringe needle may be connected to the filled syringe to deliver the medicament into a patient.
There are certain medicaments which are stored in vials that should not be physically disturbed, e.g., by inverting the vial, while accessing the medicament in the vial. Current medical practice requires the use of a relatively long cannula assembly, e.g., about 1.5 inches, to access the bottom portion of such a vial. Although, plastic needles are desirable because they present less of a risk of needle-stick injury, plastic needles are weaker than metal needles and generally can be no longer than about ½ inch in length before their diameters become unreasonably large. Thus, plastic needles cannot be used to access such vials because of their weakness.
Accordingly, a continuing need exists in the medical arts for a blunt tip cannula assembly which can access vials greater than ½ inch in depth, while at the same time being less likely to cause needle stick injuries.